Correlation of the Red Blood Cell Distribution Width with Severity and Outcomes of Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Background: Red cell distribution width (RDW) has emerged as a potential marker of systemic disease severity. This study evaluated its association with severity and clinical outcomes in acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Methods: This hospital-based observational study included 101 AECOPD presentations. RDW was compared across exacerbation-severity groups and according to ventilatory support, mortality, discharge oxygen requirement, and length of stay. Results: Mean RDW increased progressively from mild to moderate and severe exacerbations (12.91±1.26%, 14.06±1.30%, and 15.34±1.54%, respectively; p<0.001). RDW was significantly higher in patients requiring non-invasive ventilation, mechanical ventilation, and in those who died (all p<0.001). RDW correlated positively with hospital stay (r=0.433, p=0.008) and ICU stay (r=0.412, p=0.011). Its association with oxygen requirement at discharge was not significant. Conclusion: Elevated RDW was associated with greater AECOPD severity and poorer short-term outcomes.